Refrigerator-freezer



Oct. 8, 1963 e. MUFFLY 3,106,072

REFRIGERATOR-FREEZER Original Filed July 20, 1954 4 Sheets-Sheet '1 INVENTOR.

1963 G. MUFFLY 3,106,072

REFRIGERATOR-FREEZER Ongmal Flled July 20, 1954 4 sheets sheet 2 IN VEN TOR.

Oct. 8, 1963 e. MUFFLY REFRIGERATOR-FREEZER 4 Sheets-Sheet 3 Original Filed July 20, 1954 Oct. 8, 1963 I G. MUFFLY 3,106,072

REFRIGERATOR-FREEZER Original Filed July 20. 1954 4 sh t s 4 gas.

INVENTOR United States Patent 3,106,072 REFRIGERATOR-FREEZER Glenn Mufiiy, 1541 Crestview Drive, Springfield, Ohio Application Apr. 28, 1958, Ser. No. 731,300, now Patent No. 3,041,125, dated June 26, 1962, which is a division of application er. No. 444,422, July 20, 1954, now

Patent No. 2,866,322, dated Dec. 30, 1958. Divided and this application Oct. 3, 1961, Ser. No. 142,596

Claims. (Cl. 62-126) This is a division of my copending application Serial No. 731,300, filed April 28, 1958, now Patent No. 3,041,- 125, which is a division of Serial No. 444,422, filed July 20, 1954, now Patent No. 2,866,322, issued December 30, 1958.

The present application includes the claims required to be divided from the above-mentioned parent applications. These refer in particular to the refrigerator-freezer cabinet in which special provision is made for defrosting of the evaporator which cools the insulated freezer drawer, to controlling the operation of the drawer, and to related features of sealing, defrosting, defrost drip disposal and ice making.

With these and other objects in view, I now describe the drawings as follows:

FIG. 1 is a general view, partly in section, of an icemaking system adapted for use in a commercial ice maker or in a household refrigerator.

FIG. 2 is a sectional view taken on the line 22 of FIG. 1, and also showing how additional ice-making evaporators and flues or tanks may be added when it is desired to build a system of greater capacity.

FIG. 3 is a sectional view on the line 33 of FIG. 1, showing how the single and double ice disks are separated on the way to their respective storage compartments. It also shows how drip water is collected from the evaporators.

FIG. 4 is a vertical sectional view of a refrigeratorfreezer cabinet showing a system such as that of FIG. 1 installed therein and including the wiring diagram.

FIG, 5 is a horizontal sectional view of FIG. 4 taken on the line 5-5 thereof.

freezer drawer, taken on the line 66 of FIG. 5.

FIG. 7 is a top view of the upper shelf of the ice storage compar-tment of FIG. 6, showing an optional ice cutting device.

FIG. 8 is an enlarged detail of the water distributor.

FIG. 9 is an elevation of an evaporator assembly forming an ice maker without use of the tank or sleeve.

FIG. 10 is an end view, partly in section of FIG. 9.

FIG. 11 is a fractional horizontal section of another evaporator for an ice maker not requiring the tank or sleeve.

FIG. 12 is similar to FIG. 11, showing ice made in a round section instead of square.

FIG. 13 is another variation of FIG. 11, showing evaporators designed to make ice in a rectangular section.

FIG. 14 is an enlarged sectional view taken on the line 14-14 of any of the FIGURES 11, 12 or 13.

FIG. 15 shows an optional switch for use in FIG.'1 or FIG. 4.

FIG. 16 is a modified section of an evaporator.

. respectively.

3,106,072 Patented Oct. 8, 1963 FIG. 17 is a detail of a two-way switch for controlling the opening of the doors and the freezer.

FIG. 18 is an enlargement of a portion of FIG. 4, showing the gasket with drawer closed FIG. 19 shows the same gasket after the drawer has started its opening movement.

FIG. 20 shows the same gasket as it is contacted and bent by the opposite (rear) wall of the drawer while thedrawer is held in its fully open position.

FIG. 21 shows the roller slide mechanism supporting the draw-er 162 and mainly hidden back of it inFIG. 4.

FIG. 22 is an end view, partly in section, of the roller slide mechanism of FIG. 21.

FIG. 23 is a broken view of the same roller slide mechanism, but extended as when the drawer is fully open.

FIGURE 1 is a front elevation, partly in section, of an ice maker such as might be installed in a household refrigerator, with diagram of the refrigerating system and controls. Ice is formed in the tank or sleeve 10, which is here shown as open at the bottom for ice to drop out instead of float up, hence the sides taper outwardly toward the bottom. On each side of the sleeve 10 and. contacting it at spaced ice-making areas are the sheet metal evapo; rators 12, which are here shown as identical and each made of two identical stampings formed to provide the flat, round areas 14 and connecting passages for flow of refrigerant. The areas 14 of one evaporator line up exactly with similar areas of the evaporator on the 0pposite side of the sleeve 10, it being assumed'that there are only two evaporators 12 and one sleeve 10 in FIG. 1, though an extra evaporator 12 and two moreof the sleeves 10 are indicated in FIG. 2 to illustrate the fact that these evaporators are two-sided and can be placed between two tanks or sleeves to make ice in each.

Suitable headers are provided to connect the two inlets 16 and to connect the two outlets 18 with the liquid flow control device and the suction side of the compressor Water is distributed over the inner side walls of the sleeve 10 by means of the perforated spray tube'20 while the evaporators are in operation to form ice on the inside of the sleeve 10, first in small disks, which 'grow in thickness to form disks such as are indicated by the.

dotted lines at 22 in FIG. 2. After furthergrowth these disks join to form a double-thickness disk of the shape shown at 24. Periodically the valve 26 is opened to admit hot high pressure refrigerant vapor to the evapbra-i tors on both sides of the sleeve 10 to release the ice formedtherein. Preferably the flow of water is stopped while ice is being released. This is an economyfeature which will be explained later. .As the ice disks melt free from the sides of the sleeve 10 theyfall into the trough 28, of which a section is seen in FIG. 3. Doubledisks strike the ridge 30 of trough 28- and roll or slide downthis ridge and the wires 32 to the upper compartment 34 of the storage tank 36. Single disks and the halves of any'double disks that break apart as they fall will roll or slide down the trough 28 on the two sides of the ridge 30 into the FIG. 1 and assuming the refrigerator in which this apparatus is installed to have been started warm, it is obvious that switch 50, which has its bulb- 52 located in cabinet air, will be closed. Also switch 54, connected by tube 55 with its two bulbs 56 and 58, adjustably secured by spring clips 59 in the ice bins 34 and 40, will be closed until such time as both bulbs are cooled by the accumulation of ice in storage. Further, since not much ice has accumulated in the upper bin 34, there is not enough weight on shelf 69 so that the portion of this weight carried by the rod 62 will compress spring 63 and move the switch 64 to its closed position. The collar 65 is adjustable on rod 62 to vary the Weight of ice required to close switch 64. The fact of switch 64 being open means that closing of switch 66 closes no circuit, hence we can consider only the effect of the closing of switch 63 in response to the rotation of cam 70, which is assumed to be driven steadily at one revolution per hour.

During all of the hour except the two or three minutes that switch 68 is closed, the current flow from line '72 is through switch 54 to wire '74, through water pump motor 76, wire 7%, switch 8% and back to line '82. At the same time current flows through switch 54 to wire 84, through the motor of motor-compressor unit 36 and back to line 82. The former of these two circuits is broken as a result of the closing of switch 63, but the latter is constant, thus keeping the compressor running during the ice-releasing period. Now we consider the effects of closing switch 68, which connects wire 74 with wire 87 to energize solenoid 88, which opens switch iii to stop motor 7-6 and at the same time lifts valve 26 to open the path for hot gas to how from condenser 90 and unit '86 to inlet 16 of the evaporators on both sides of sleeve 10. This heats the spots on which ice has been formed and releases the double disks of ice, which roll into the bin 34. It should be noted that switch 50 plays no part in this and can be either open or closed so long as switch 54 remains closed. Also note that nothing happens when the cam 79 closes switch 66, so long as switch 64 is open.

Now let us consider what happens when the weight of double disks of ice on shelf 60' causes switch 64 to close. The operation continues as before except that solenoid 88 is energized for two short periods in each hour, thus causing the release of ice to occur while it is still in the form of single disks 22, which fall into bin 40 instead of bin 34. It is assumed that the switch 64 is so adjusted that it does not close until the ice disks 24 in bin 34 have covered the bulb 56, hence when the ice disks 22 in bin 40 cover bulb 58 both bulbs will be chilled to nearly 32 F., at which point switch- 54 opens. The volatile fluid charge of 54, 56 and SS is in such quantity that its liquid portion will more than fill one of the bulbs and partly fill the other, hence both bulbs must be chilled down nearly to 32 F. in order to open switch 54. When either of these two bulbs warms up as a result of ice removal, the switch 54 recloses and ice production resumes, making single disks 22 if switch '64 is still closed, but making'doubl-e disks 24 if switch 64 has meantime opened as a result of the removal or meltage of ice from above shelf at When switch 54 opens in response to the accumulation of a full supply of ice the switch 50 may or may not be opened, depending upon whether or not bulb 2, located in the air within the refrigerator, has been cooled down to the desired cut-out temperature. In case the switch 50 is closed at the time switch 54 opens, or in case switch 50 closes at any time while switch 54 is open, the effect is to allow current to flow from line 72' to wire 84, through the motor of 86 and back to line 82 thus operating the compressor and cooling the air within the refrigerator. It is noted that when switch 54 is open the motor 76 is not energized, hence water pump 92 is idle and no water is delivered to the spray pipe 25 In this case only air contacts the evaporators l2 and the 4 sleeve 10, which acts as extended surface to aid in cooling the air.

During the freezing of ice there is a constant flow of water from the spray tube 21 and the unfrozen portion of this water falls into the trough 28 in which there are many small holes 92 for the escape of water into the lower trough 94, from which it drains through tube 96 to the compartment '44 of the tank 36. The movable shelf es and the similar shelf 98 forming the bottom of bin 4%) are perforated or otherwise open to allow water of meltage to flow from bins 34 and 49 into the lower section 44 of tank 36 and it is preferred to make the side walls of this tank water-tight up to a level which will accommodate any unusual ice meltage such as that occurring when current is off. A door or hand hole opening above this level is provided in the front of compartment 4t} and if desired such a front opening may also be provided for the upper bin 34.

Within compartment 44- is a float 102 which opens the valve 164 to admit Water when the level drops below normal due to making ice or drawing water from the faucet 1%.

FIGURE 2 shows in addition to the section of sleeve 10 and the two evaporators 12 sections of additional sleeves it) and an additional evaporator 12', which may be assembled in the positions shown when it is desired to use two or more similar sleeves in one assembly to construct a machine of larger capacity, using mostly the same parts. The evaporators 12-12 are shown as made by welding together two identical stampings, which puts the contact spots of the two stampings in parallel planes, hence the sleeves 1h are slightly inclined from the vertical position of sleeve 10. This is permissible when only three or four sleeves are assembled together with the double-sided evaporators between, but in the case of still larger assemblies it may be advisable to viding the die with removable inserts to alter the positions of passages which connect the end ones of flat areas 14.

Another design, which allows the evaporator stampings to remain identical, is to eliminate the taper of the sleeves it). This calls for care to see that the sides of the sleeves are flat-and parallel to avoid sticking of the ice after its release. The choice will depend in part upon the number of horizontal rows of ice-making areas and whether the hot gas for releasing ice is introduced at the top or the bottom of the evaporators.

This will be discussed further in connection with the figures appearing on sheet 3 of the drawings.

FIG. 4 is a vertical sectional view of ahousehold refrigerator of the two-zone type, showing location of the ice maker of FIG. :1, with diagram of the wiring system. The type of cabinet shown is that of my copending US. application Serial Number 235,920, filed July 10-, 1951, now abandoned, of which continuation S.N.- 705,157 was filed December 26, '1957, and issued August 30, 1960, as patent US. 2,950,911 and is assumed to be equipped with similar operating mechanism for the two main doors.

The lower portion of the cabinet, including the freezer drawer, is similar to my patent US. 2,709,343, issued May 31, 1955, and patent US. 2,765,633, issued October 9, 1956, but shows an improved form of operating mechanism and defrosting system.

The wiring diagram of FIG. 4 differs from that of FIG. 1 mainly in showing additional connections for the freezer drawer and its evaporator. When the plug is inserted in a live outlet and the refrigerator has been entirely cooled down, including the making of a full supply of ice, the various controls will be in off position and the only portion of the system energized will be the clock 112, which runs all the time. Assuming now that the air in the main food space 114 first calls for cooling, the warming of bulb 52 causes switch 50 to close, whereupon current flows from line 72 over the wire 120 to switch 50, thence to the wire 122 and through freezer control 124 and wire 126 to the motor-compressor unit 86, returning over wire 82 to the line. This starts operation of the system to cool the evaporators 12, but does not energize the pump motor 76, hence no water flows over the ice making surfaces and the evaporators cool only the air of the space 114, which is free to flow over the cooling surfaces. During this operation there will be some frost formed on the evaporators,.but it will melt off during the next idle period and drip into the two gutters 42 (FIG. 3), located on opposite sides of the ice chute 28, from which it drains to the heavy corrugated base .pan 130 and evaporatesto room air. This defrosting of the ice-maker evaporators also occurs between runs of the ice maker, while ice is being released, thus separating the drip water condensed from the air. from the water to be used in making ice and avoiding the collection of food tastes in the ice.

Either during the run for air cooling or after it has been completed, let us assume that the ice-maker switch 54 closes in response to the reduction of the ice supply in either the upper compartment 34 or the lower compartment 40. This will occur in response to the reduction of either ice supply due to the fact that the liquid portion of the charge of switch 54 is sufiicient to fill one of the bulbs 56 or 58 entirely with liquid and only Suficient to fill the other (warmer) one of the two bulbs partly with liquid, while the balance of the control, including the tube 55 and the bellows or similar expansible space of the control, is filled with vapor only. Thus the response which starts making ice is to the warmer one of the two bulbs which is not suflicieutly covered by ice to hold it below the cut-in temperature.

At the time of closing of the thermostatic switch 54,

of the ice maker, assuming that the upper compartment 34 contains a full supply of ice, the weight switch 64 will be closed, as shown in FIG. 4. This means that the cam 79, rotated one turn per hour, will alternately close circuits through switches 66 and 68 at half-hour intervals. Each switch remains closed for a fixed period of say two minutes, allowing about twenty-eight minutes of ice freezing time between the releasing periods. This causes a thin disk of ice to be formed on each of the opposed icemaking spots and a double number of pieces of ice will be released before they have joined to make half the number of double-thickness disks. Upon closing of either switch 66 or 68 the solenoid 68 will be energized to open the switch 80 and stop the water pump motor 76. At the same time the solenoid 134 (in parallel with 88 so operation is the same as in FIG. 1) is energized to open the hot gas valve 26, allowing hot, high-pressure refrigerant vapor to enter the evaporatons 12 through the tubes 16. While this defrosting to release ice occurs the compressor continues to operate, supplying hot gas for the defrosting. Upon re-opening of the closed switch 66 or 68 the valve 26 and the switch 80 are reclose d by gravity, thus restarting the cooling of the ice-maker ev-aporators and the operation of the 'water pump.

Assuming now that during the ice-making run, as above outlined, some ice is removed from the upper compartment 34 containing the double-thickness disks. This will lighten the load on shelf 60 and may allow the spring 63 to lift it and open the switch 64 to break the circuit through switch 66 and thus prevent one of the half-hour ice-releasing periods from occurring. This lengthens the ice-making period to about 57 or 8 minutes and causes the formation of ice in the double-disk size. Because slightly more time may be required to release the doublethickness disks, it may be advisable to keep the switch It will be understood that the.

actuated by the cam-142, driven at a much lower speed I which may be one to seven days per revolution.

During all of the ice-making operation of the system, the ice disks which are released fall into the trough 28, which has a section shaped like the letter W. Single thickness pieces of ice fall into one side or the other of this trough and roll or slide into the lower ice-storage compartment 40 by way of the chute 38 leading to it. Double-thickness disks falling into the trough are supported by and slide'or roll on the middle ridge 30 of the trough and are thereby guided-into the upper storage compartment 34 by the wires or rods 32. Should any double-' thickness ice of less than standard weight be formed dur which'provi'de for stopping the ice-making periods ex'-.

actly at their ends to insure the making of only full-sized ice.

is not energized and therefore it closes the inlet of tube 148 wh=ich carries liquid refrigerant to the freezer ex pansion valve 150. Also check valve 152 prevents refrigerant vapor from flowing back into the evaporator 144 to be condensed therein. Note that freezer control 124, as shown in FIG. 4, is merely closing contacts in the ice making and cabinet air cooling circuits for openation of the evaporators associated with the ice maker, and that all connections with solenoid 154, heater coil 156, and switch '138 operated by the clock, a're'broken in the double-throw double-pole switch of the control 124. The

only elements of the freezer portion of the cabinet which can be energized automatically with the control 124 in the position shown are the lamp 158, which is turned on by the-switch whenever the drawer 162 is opened, and

the motor 164 which opens drawer 162 when switch 166 is manually moved to the dotted position. At all'times' the lamp 1-68, located within the main food space 114 of the refrigerator, is turned on by the swtich 170 when either of the two doors are opened, in line with the com mon practice.

Assuming now that the freezer bulb 172, located with" in the recess 174 of the cabinet floor, warms up to the cut-in point of the freezer air temperature and actuates the control 124 to move both of its switch blades to theirdotted positions. This will occur when the warmer portion of the air within the freezer reaches the cut-in tem-" perature, which may be near 0 to 10 F. The resultand to the motor 164 which actuates the drawer during the defrosting of evaporator 144.

Que effect ofthe operation of control 124 to the dotted positions of the switch blades is to close the circuit through-wire 176 to energize the solenoid 154 and lift the valve which opens the passage for liquid refrigerant" to flow from the tube 178 to the tube 148 leading to the expansion valve 156, thus starting the cooling of evaporator 144 to the required lower temperature than is gen-' erally deslred in theic'e-making evaporators which also cool the mam food space 114 of the refrigerator. Simultaneously with the start of liquid flow to evaporator 144 the-compressor circuit is closedto start or continue its operation. Normally the cooling of freezer evaporator- 144 will continue until-the bulb 172 is cooled down to the deslred cutout point, which may be from +10? to 20 F. During operation of evaporator 144 it will-be 7 During all operation of the ice maker and of its evap'o rators to cool cabinet air, the evaporator 144 of the freezer will remain inactive because solenoid valve 146 seen that the colder air drops into the drawer to cool the frozen foods contained therein and that warmer air flows from below the shelf 180 upwardly through the flue 182,

which is divided from the frozen food space by the wall 184, which may be of insulating material. This upward flow of the warmer portion of the cold air strikes the bulb 172 and when this air temperature has fallen to the desired cut-out point the control 124 is actuated to return to the positions shown by full lines in FIG. 4.

The above description assumes that no defrosting of the freezer evaporator has occurred during the operating cycle of evaporator 144, as this defrosting happens at widely spaced intervals. It will be seen that switch 138 is closed by cam 142 once during each rotation of the clock shaft which carries it. This shaft is the tubular one, as commonly used in clock construction to drive the hour hand or a still slower hand showing days of the week. It is preferred to use a clock mechanism designed for a 24-hour hand or a day-of-the-week hand, while the cam 14-2 is quite sharp-pointed and the switch 138 is adjusted in position (by means of screws 1816 and their slots) to allow only a few minutes during which the circuit is closed through wire 183 to the heating coil 156, located below the tubes of evaporator 144 in good thermal relationship to them. 7

The freezer drawer is mounted on a roller slide mechanism usually comprising three channel members of which one is fixed to the cabinet, one fixed to the drawer and one floating between on rollers. The usual hump which retains the drawer in closed position is here duplicated at the full open position. It will be seen that when switch 138 is closed it also completes the circuit through switch 166 and motor 164, which is preferably back-geared to the shaft 190 carrying the sprocket wheel 192 in such a manner as to be reversible. Upon energizing of motor 164 the shaft 19% is rotated clockwise, moving the inclined belt or chain 194 to carry the lug 196 against the racket 198 mounted upon the rear of the drawer 162 and extending to the far (left) side of the drawer into the path of the lug 196. This pushes the drawer in the opening direction on the roller slide mechanism of which outer channel 200, fixed to the outer shell of the cabinet, provides the track for the floating member 202 which carries rollers supporting the track 203, attached to drawer 162. This action first pushes the drawer off of the humps of 203 which lift the drawer as it closes, letting it drop to the position 162. Further chain travel pushes the drawer to the nearly full open position 162,", where the drawer is slightly elevated above its closed position by virtue of the inclined track 2490 on which it is guided and supported. At this point 162", the second lug 204 strikes the stop 206, which is welded to the far (left) side of the outer shell of the cabinet and thereby causes the motor 164 to stall, the motor being designed to stand such a locked-rotor condition for the required length of time. The motor remains stalled, holding the drawer open at position 162", during the few minutes required to defrost the freezer evaporator. Defrost water thus falls into the heavy metal pan 130 which forms the main base of the cabinet instead of falling onto the frozen foods in the drawer. Upon completion of the defrost period of predetermined length the switch 138 reopens, st pping the heating of coil 156 and deenergizing the motor 164-, whereupon cooling of evaporator 144 resumes and the drawer recloses under the influence of gravity due to the inclination of the track upon which it is carried by rollers This inclination is sufficient to cause the inertia of drawer reclosure to lift the drawer from the position 162 to the fully-closed position 162 in which it is shown by solid lines.

When the cam 142 makes one revolution per twentyfour hours the switch 138 closes once a day, preferably at two or three oclock in the morning, when it will not interfere with normal operations in the kitchen, but as a safety precaution in the event that someonecomesv into the kitchen in the dark and might fall over the open drawer, I have provided the switch 160, which is located on the far side of the drawer in hidden position, to be closed when the drawer is part way open and remain closed until the drawer is nearly closed, thus causing the lamp 158 to be lighted whenever the drawer is opened, either automatically or by hand.

Since it is not normally necessary to defrost the freezer evaporator at such short intervals as one day, the wiring is so arranged that the defrosting occurs only when the control 124 is in position to allow the freezer to operate. Thus the defrosting will be more frequent when the freezer is being cooled more frequently, thereby increasing the probability of a defrost. If during the night the freezer control is on one-eighth of the time the freezer evaporator will be defrosted about once in eight days. On other nights the drawer will not be mechanic-ally opened nor the defrost heater energized. Since it should not normally be required to defrost the freezer oftener than once a month, this provision is ample. At the end of each freezer defrost the bulb 172 will be warmer than usual, which means that the cooling of the freezer will always oontinue after the defrost until the air rising from the drawer through the due 182 is again down to the cutout temperature. In case a seven-day or a thirty-day shaft is used to drive the cam 142, the wiring can be changed to cause a defrost each time the switch 138 is closed.

For normal access the drawer 162 may be pulled open by hand to the position 162" shown by dotted lines, at which full-open position it is retained by a hump in the track similar to that which keeps the drawer in its closed position. This opening of the drawer does not cause defrosting, but it does light the lamp 158 to aid in seeing the drawer contents. A slight push moves the open drawer off of the hump to the position 162", from which it is reclosed by gravity. The chain 194 and its lugs do not move when the drawer is opened by hand.

An optional feature, which may be added if desired, is the switch 166, by means of which the user may energize the motor 164m any time, causing the drawer to be opened by power and held open until the switch is snapped back to the solid line position to allow the drawer to reclose under the influence of gravity, all without energizing the heater coil 156 and regardless of what controls may be on or off. This is a refinement toaccompany the power opening and closing of the two upper doors of the cabinet, as described in copending applications of mine listed above. The switch 166 is preferably located beside the lamp 158 or in the face of the cabinet at a higher level, out of reach of small children, and is arranged to snap from one position to the other. It will not interfere with defrosting nor with any other functions which are time or temperature controlled, except that the freezer drawer can not be cooled while open. To provide against carelessness of the user in forgetting to reclose the drawer, the switch 166 may be of the timing variety, such as those used on electric toasters, so that the drawer will be closed automatically at the end of a pre-selected time limit. The same provision can be made for the mechanical reclosing of the two main upper doors in combination with the mechanical self-opening feature disclosed in my earlier patent applications above listed.

The mounting of the drawer 162 on rollers with an inclined telescoping track and the humps, which slightly lift it at the fully closed and fully open positions, is shown in FIGURES 21, 22 and 23, and will be understood by reference to the similar telescoping tracks, usually of channel form, which are commonly used on letter file drawers. zontal and normally have the humps at the closed position only. The difference here is that I propose to mount these tracks on a slight incline to lift the drawer as it is opened, and to locate the humps at both ends of the travel, so that the drawer is slightly lifted and retained in position by the humps in both its closed and its fully In the case of letter files the tracks are hori- 9 open positions. The nearly-open position 162" of FIG. 4 is just prior to the lifting of the drawer which "occurs as it is moved to the fully open position 162" in which it is retained. 7

Use is made of gravity and of the power of motor 164 in breaking the drawer free from any ice or frost which has formed on the top edge of the drawer and on the gasket. The new type of gasket shown at 210* is provided to facilitate this breaking free as the drawer is opened either by hand or under power. The thin flexible ribs 212 of the gasket are bent to the positions shown by the closing of the drawer, hence are so curved as to tear away readily from any frost bond between them and the drawer. The initial movement of the drawer from the FIG. 18 position in the opening direction will flex these ribs and then the dropping of the drawer off of the hump to the position 162' (FIG. 19) will further aid in tearing the gasket free. Since the cabinet width is commonly about twice the inside front-to-back depth of the freezer drawer this takes care of most of the gasket. .A similar effect is obtained where the gasket is in contact with the near far ends of the drawer as seen in FIG. 4 by forming the gasket with zig-zag ribs at an angle of say 45, as seen in FIG. 6. This, in conjunction with the inclined tops of the end walls of the drawer, makes it relatively easy to break the drawer free from any freezing shut that may occur. The use of a plurality of ribs also raids in this by preventing kitchen air from reaching the coldest of the ribs.

Assuming that the cabinet air switch 50' recloses in response to a rise of temperature in the main food space and ice-maker switch also re-closes in response to a demand for more ice while the freezer is being cooled (with or without defrosting evaporator 144) and then the freezer control goes back to the position shown by solid lines in FIG. 4, the effect will be to start making ice, which also acts to cool the air in the food space. The first pieces of ice made are apt to be small pieces, due to the accidental stopping of the latest run in the middle of an ice-making cycle, but the next batch of ice will be double disks if any are required to reclose the switch 64.

If switch 64 is already closed because of the upper compartment being full, the first complete run on ice making will be to make a batch of the single-thickness disks.

Should operation of the ice maker cool the cabinet air touching bulb 52 to the extent of causing switch'50 to reopen, the compressor will stop when the demand for ice is satisfied, otherwise the system will continue to operate on cooling the ice-maker evaporators with the water pump idle, thus completing the cooling of cabinet air to the desired cut-out temperature. Because the stored ice is at exactly 32 F. and ice making includes defrosting, there is no danger that the continued operation of the ice maker will cause foods stored in the main compart- 114 to freeze.

FIGURE is a top view taken on the line 55 of FIG.

4, showing the locations of the ice maker and the ice" storage compartments as Well as the type of double front doors referred to in the specification. It will be noted that the removable wall section 218 need be only of the size shown to allow removal of the entire refrigerating system from the cabinet. Comparing this view with FIG. 4 it will be seen that the motor-compressor unit 86 discharges through compressed refrigerant vaporv through the tube 220 leading to the condenser 90 except at such times as the solenoid valve 26 is open for the hot gas to flow into the ice-maker evaporators 12. From the liquid receiver 224 at the bottom of the condenser, liquid flows normally through tube 226 to the expansion valve 228 of the ice maker, but when solenoid 154 is energized to actuate the valve 146, allowing flow to the .tube' 148 and.

stopping flow to tube 226, liquid flows through tube 143 to the expansion valve 150 of the freezer.

Vapor returning from the ice maker evaporators flows through the tubes 18 and 230 to the suction side of the compressor. Meantime the check valve 152 prevents the vapor which leaves the ice maker evaporators from entering the colder freezer evaporator. When the freezer evaporator is operating the valve 146 closes the passage between the liquid tube 178 and the liquid tube 226, thereby preventing flow of liquid refrigerant to the ice-maker evaporator-s. The system operates at either the very cold or the moderately cold temperature, according to the needs of the main and the freezer compartments, with the result that higher efiiciency is obtained than in systems wherein the compressor must always operate at the lowest suction pressure employed in the system.

Drip water collected from defrosting of all of the evap orators falls into the pan and from there is evaporated to room air with the aid of the mat 234 which by capillary action spreads the water in the path of the air flow induced by the stack elfeot of the condenser, which forms a chimney 236 up the rear of the cabinet. With ample air flow thus induced and a suitable mat for picking up the water it is not necessary to provide for heating the pan of water, but this is easily done by extending one of the hot tubes into the pan, if it is thought to be necessary. v

The drain tube 238 rdelivers drip water fromthe lining of the cabinet where collected in the gutter 24% and also from the two gutters 42, as seen in FIG. 3, to the fabric 234 from which the drip evaporates to room This fabric is of a nature to carry water up from the base pan 130 by capillary action to evaporate into the air stream induced by the up-draft in the chimney 236.

The freezer drawer is preferably made with its side walls and bottom thicker or better insulated than other walls of the cabinet, there being no insulation in the cabinet side walls at the level of the drawer. This insures that the frozen foods in the drawer will not be star-ted to thaw during any normal periods during which the drawer is open. The bottom of the main food space, directly above the freezer evaporator, need not be heavily insulated because leakage of heat from the main food space into the freezer only aids in cooling the lower portion of the food space. It is only necessary to see that foods in the bottom of the main food spacedo not freeze.

The compressor may be allowed to run during both ice release and freezer defrost periods. leasing ice and causes no serious loss of efiiciency during freezer defrost due to the very small percentage of the time thatthe freezer evaporator is on the defrost portion of its cycle. frosting can be employed for both the freezer and the ice maker by some duplication of parts. It will be seen that liquid will not flow through the expansion valve '150 to the freezer evaporator while it is being defrosted and any pressure within the evaporator 144 in excess of that in the suction tube 226 will flow through the check valve 152 and be drawn in by the compressor.

When a refrigerator is installed in most kitchens it is found that some levelling up is necessary. Usually four dome-like feet are provided with screws for making this adjustment, but they take up some of the height and are not easily accessible for adjustment. 1 have therefore shown the two rear domes 242 as stamped into the heavy metal of the drip pan 130 which forms the base of the cabinet and have shown similar domes in two small stampings 244 to be Welded to the botom of the pan at its front. These front domes 'are' adjustable in height by means of the lwedges 246, which may be driven in from the front as required. The wedges are preferably slotted to be held in place by small tongues on the stampings 244 as the sta mpings are spot-welded to the pan. The adjustment thus provided should be sufiicient to tilt the cabinet forward as well as backward at either front corner, thus providing the full range of adjustment for any ordinary condition of floor unevenness. Very slight serrations This aids in re-- If desired the same method of hot gas decrosswise of the upper side of each wedge and in matching positions on the bottom of the pan will prevent the wedges from working loose after they are once adjusted.

Switch 245 is a service provision for emergency d frosting. It is manually closed and self-opening by means of a clock or thermal release. When closed it starts a defrost period of the freezer evaporator, including the opening of drawer 162 if it is not already open. At the end of the timed defrost period the switch 243 snaps back to its normal position. This switch is seldom used and may be omitted, as service men can produce an artificial defrost period by other means when required.

FIGURE 6 shows the freezer drawer gasket 210 as seen from the bottom of FIG. 4 with the drawer 162 re moved. The only part of the cabinet shown in section is the right-hand side of the outer shell, which is continous to the base pan 130 of FIG. 4. Looking upward into the recess 17%, which houses the freezer evaporator, we see the gasket 21% and its flexible ribs 212, portions of which are made in zig-zag fo'rm 212 where extending from front to back. The reason for this is to retain in these front-to-back portions of the gasket as much of the flexibility of the crosswise ribs 212 as is possible. Due to the height, thinness and flexibility of these ribs and the fact that they bend sidewise as the drawer is closed, they are easily torn free from the top of the drawer as the drawer is opened, first dropping and then moving forward. At the right, rear corner (from in FIG. 6) the gasket is cut at 252 and the ends secured by means of screws or other fasteners 254. This allows a portion of the gasket to be released'and bent back for removal of tubes and wires associated with the evaporator 144', the bulb 172, and the heater coil 156, which connections are located in a notch covered by the gasket. The zig-zag portion 212' of the gasket is located directly above the side walls of the freezer drawer, leaving a plain portion of the gasket 210 exposed above the side spaces between the drawer and the side walls of the outer shell of the cabinet, the gasket also serving as a thermal breaker between the outer shell and the pan-shaped lining of the recess 174.

FIGURE 7 shows a modification of the upper ice shelf 6t, here identified as 6% and equipped with resistance wires 256 to which very low voltage current is supplied by the transformer 258 under control of switch 266, which is connected with the line 72-82. This switch may be manually operated or made responsive to variations of ice quantity in compartment 40, using one of the methods which I have previously disclosed, to obtainan increased supply of ice in small pieces. In FIG. 7 I have shown the hole 62' located at the rear end of shelf 66!, which means that the control 64 and rod 62 are located at the rear end of storage tank 36 instead of at one side, as in FIG. 1, putting them more out of the way.

FIGURE 8 shows the upper portion of a sleeve 10'', which is similar to it) of FIG. 2, with the sides extended upward and outward to accommodate the tilting water distributor 262, carried by the freely supported shaft 264, which rests in notches 265. This distributor is shaped to form two troughs and is free to rock from the extreme left position shown to a corresponding position at the right, being stopped each way by contact of the notched edge 266 with an angular side portion of Id. In the position shown, water from the left hand trough flows as indicated by the curved arrow through the notches at 266 to wash over ice being formed on the left; side of sleeve 10 while the right hand trough is being filled with water from the tube 20', which in this case has one row of holes 268. Meantime some of the water escapes from this trough through a number of quite small holes 270 to drip into 10" andonto the ice being formed therein on the right side. The pattern of this 'drippage can be modified by the hole locations and their relative sizes, but the total of such dripp age is considerably less than the rate at which wateris supplied through the holes 268,

1% hence the right hand trough fills with water and the weight of this water finally causes the distributor 262 to tilt to its extreme right position, dumping the accumulated water down the right side of the sleeve 1% and over the ice being formed on that side.

This intermittent flushing of the ice, first on one side and then the other, produces a better washing of air bubbles from the ice surfaces than a steady flow of the same average volume and allows a short interval between the surges of water for the water which adheres to the ice to solidify, with the result that ice of clearerquality is frozen more rapidly.

7 FIGURE 9 is a side view of a modified evaporator 272, which is paired with a similar one hidden by it. This figure will be better understood by reference toFIG. 10, which is an end view of the assembly with one of the evaporators shown in section, on the line 1difi of FIG. 9. Low pressure refrigerant, mainly in liquid phase, flows from the expansion valve or r-estrictor through the tube 274 and associated header to the inlets of the evapor-ators at the top and refrigerant vapor leaves through the lower header and tube 230.

The evaporators 272 are similar to evaporators 12 of FIGS. 1 and 2, but are made thicker at the top so that a considerable number may be assembled in a group without the progressively greater tilt indicated in FIG. 2. Another feature, best seen in FiG. 10, is the elimination of the tank or sleeve such as it) and it) of FIG. 2. This is accomplished by covering each evaporator with an insulating jacket 276 of a plastic material which acts as a thermal insulator and is impervious to water. It is preferably a substance which handens with a smooth surface and to which ice does not readily adhere. There are many rubber and plastic materials of suitable nature and most of them have the characteristic of shrinking slightly as they harden, which is desirable because it insures that the areas between the surfaces 14 of the ev-aporators do not project beyond the plane of the surfaces 14.

By eliminating the metal walls between the evaporator-s and the ice and using thethermaily non-conducting material to form the jacket 276 the shape of the ice is moditied in the direction of reducing the diameter of the disks and causing them to build faster in thickness, hence the diameters of the areas 14- are increased on evaporators 272 as compared with evaporators 12 for a given diameter of ice disks, thereby effecting a further increase in the rate of ice production. t is also possible, because of the material forming the intervening areas being non-conductive, to place the areas 14- closer together in FiG-S. 9 and 10 than in FIGS. 1 and 2 without danger of the separate ice disks joining each other across the surfaces to such a degree that will not break apart as they fall upon being released. These features adapt FIGS. 9 and 10 for use in commercial ice makers, whereas FIGS. 1 and 2 are better adapted for use in household refrigerators, where ice-making capacity is not so important and it is advantageous to expose more of the evaporator surfaces for the purpose of cooling the air within the refrigerator.

FIGURE 10 also shows the use of the tilting distributor 262 for water, as shown in more detail in FIG. 8. As in FIG. 8, the shaft 264 of 262 is preferably supported in notches so that it may easily be lifted out of place for introduction of a double-sided brush to clean the icemaking surfaces. It is also desirable to provide a swivel or flexible connection, such as hose 277, for the tube 20 or 24) so that it may be swung or lifted out of the way for the same reason. In FIGS. 8, 9 and 10 the tube 20' and the shaft 264, of which the former is considerably larger in diameter, are shown supported in the same stepped slots 265. The tube 2% is slightly flattened so that the upper section of the slot 265 holds it from rotating. In FIG. 8 the slots are made directly in the end walls of the sleeve 10", while in FIGS. 9 and 10, having no sleeve, the slots 265 are in the brackets 273.

The choice as to whether liquid refrigerant enters the 13 evaporator at the top, as in FIG. 9 or at the bottom,'as in FIG. 1, depends in part on size of the unit, in part upon whether the ice is floated up or dropped down, and in part upon the method used for heating the evaporator to release the ice. In a large unit of commercial type similar to FIGS. 9 and 10, but probably having many more ice making areas on each evaporator, with ice dropping out of the bottom, it is preferred to use the hot liquid method of releasing ice, as shown in some of my issued patents such as U.S. 2,672,016 and 2,672,017, issued March 16, 1954, and U.S. 2,774,223, issued December 18, 1956, U.S. 2,795,112, issued June 11, 1957, and 2,787,890, issued April 9, 1957. However, in the present application the emphasis is on letting theice drop instead of floating it out the top of a tank hence it is preferred to release the bottom row of disks first, introducing the hot gas or hot liquid at the bottom of the evaporator. When the flow of liquid is reversed to release ice, as in some of these earlier applications of mine, this then means that during the cooling portion of the cycle low pres sure liquid enters at the top and during the ice releasing portion of the cycle hot liquid enters at the bottom.

FIGURES 11, 12 and 13 are quite similar except that they show the making of ice in square, round and oblong cross sections, respectively. These differ from FIGS. 9 and 10 in using one entire side of the evaporator for ice contact instead of using only the raised areas of each side. They also differ in producing ice of fixed shape with fixed dimensions in the plane of the drawings, as shown at 291 291 and 292, yet they can also be used with the short cycle to make two thin pieces instead of one thick piece of ice.

The two evaporators which form any of these three FIGURES 11, 12 or 13 are identical, each being formed of two stampings Welded together where the two sheets contact each other. Several such pairs of evaporator elements are stacked, one above the other, as shown by FIG. 14, which is a section of. any of the three, as indicated on FIGS. 11, 12 and 13.

'Ice forms on each evaporator and then joins, leaving an opening 284 through which water flows, thus there is no hole in the ice cube, but a groove on each side. The rubber or similar spacers 286 are poor conductors of heat, hence ice is very slow to form on them, and the same is true of the spacers 288- (FIG. 14) which separate the evaporators as stacked one upon another. 7

FIGURE 15 shows a switch 296, which is of the snapover variety, arranged to stay in either open or closed position. It is connected by means of rod 298 with shelf 98 of FIG. 1 and its spring eifect is adjusted so that a full supply of ice on shell 98 will move it to the open posi tion shown. It stays in this position except when manually moved to the dotted position, in which it shorts out switch 64 of FIG. 1 or FIG. 4, thus causing the ice-maker to operate on the short cycles, making only.single-thickness disks of ice until compartment 40 is full and shelf 98 weighted heavily enough to open switch 296 so that switch 64 again becomes effective and the ice-maker returns to its normal operation of filling compartment 34 with double disks before making more single disks.

The purpose of switch 296 is to enable the user to hasten the making of the single-thickness disks of ice when there is a special need for them. At the same time it may be desired to close switch 2600f FIG. 7 for the purpose of reducing the double disks already on hand in compartment 34 to smaller pieces. The rod 298 may be so con nected that the weight of ice on shelf 98 opens both switches 260 and 296 to stop both the making of small pieces of ice and the cutting of large pieces into small size when shelf 9-8 supports slightly more than its normal maximum load.

. It will be noted that in FIG. 4 I have shown the motor-, compressor unit 86 located at the top rear of the cabinet instead of at the rear of the freezer drawer as in patents U.S. 2,709,343 and U.S. 2,765,633. The main reason 14 for this is to increase the front-to-back inside dimension of the drawer and thus provide more storage space for frozen foods. I further propose to make the outside frontto-back dimension of the drawer greater than the corre sponding dimension of the upper portion of the cabinet and to indent the rear outer wall of the drawer to provide room for the motor 164, which generates very little heat as compared with the unit 8 6, thus providing still more freezer capacity in a given height. It is also proposed that instead of making the freezer walls thicker they be insulated with a better insulating material, even though this is more expensive than the insulation used in the balance of the cabinet. 7

FIGURE 16 illustrates a modification of the evaporator 12 which may be used when economy of space is more important than the economy of using one die to form both of the sheets which make an evaporator. This modification is particularly applicable when the icemaking areas 14 are separated by the plastic material 276 and no tank or sleeve 10 is used. By staggering the embossed spots on one side of the evaporator relative to those on the other side it is possible to make one embossment form the refrigerant passage between two of the embossments of the other sheet.

This same idea of FIG. 16 also applies to evaporators on the order of FIGS. 11 to 14, in which case the vertical lines of adjacent rows are staggered and nest together, which is particularly obvious with reference to FIG. 11. It will also be understood that the insulation 286 and 288 may be omitted if the evaporators are covered with plastic 276, leaving only the ice-making areas exposed, as in FIGS. 9 and 16. In that case the plastic 276 may form the divisions between vertical fines, or these vertical separating members may be omitted if other means is provided to support the two adjacent evaporators with the proper spacing between them.

FIGURE 17 shows a switch mechanism which may be mounted on the outer side of one of the doors, onboth doors, or on the outer shell of the cabinet beside one or both doors. The rocker 304 is designed for actuation by the users arm contact. It is pivotted to the bracket .306 and may be retained in the neutral position shown by means of a spring 308. The bracket 306 is pref erably welded to the outer shell of the cabinet or door in a depression 310 formed therein. Assuming the rocker to be located vertically on'a horizontal axis as shown, the user pushes on its upper end to close switch 312, which corresponds with the switch 112 of my copending U.S. application S.N. 235,920, filed July 10, 1951, now abandond. This switch need be held closed for only a fraction of a second to start the opening of the two doors, whereupon the doors are fully opened by power as explained in this copending application. user desires to open the freezer drawer she presses on the lower endof rocker 304 to close the switch 314. This switch, unlike 3'12, stays closed after being pushed in and includes a spring motor or electrical means for holding it closed for a preselected length of time, after which it snaps back to its normal open position. The switch 314 is similar'to switch 166 of FIG. 4 in this respect and is connected to energize motor 164, this causing the drawer 162 to open to the position 162", where it remains until the switch 3'14 snaps back to its open position, allowing the drawer to reclose. It is thusseen that the user, coming to the refrigerator with both hands full, can open either the drawer or the doors by a touch of her'elbow on the rocker 304. She can, in fact, open both the freezer drawer andthe doors by pushing on the lower end of rocker *304 and then on its upper end. The drawer will reclose itself and the doors will reclose in response to slight push on either door, as explained in the earlier application S.N. 235,910.

The shaft 11 of FIG. 4, or the speed reduction gearing through which 'motor 164 drives 190, .is preferably equipped with an energy storage device such as a .coil

If, however, the 7 spring surrounding shaft 190. This spring is energized by the rotation of shaft 190 in the direction which opens the drawer 162 to position 162. When the motor 164 is de'energized this spring rotates shaft 190, the gearing and motor 164 in reverse so that the frictional load of such reversal need not be carried by the gravitational force which recloses the drawer. If desired the lug 1.96 may be linked to the bracket 193 so that the spring pulls the drawer 162 closed instead of merely getting out of the way of the gravity closing of the drawer. In this case it would not be necessary to incline the elements 2ili3-28 2 and the hump at full-open position 162" could be omitted, but I prefer to retain the inclined track and to keep the drawer free from the lug 196 so that the drawer can be more easily opened and closed manually when desired or in case of current failure.

While I have described the power element 112 as a clock and referred to cam 7% as makingone revolution per hour, it is under stood that cam 70 may be driven at any desired speed and that the speed may be adjustable to provide longer or shorter cycles of the ice maker. For instance the variable resistance or other controller 3 2% may be connected as shown in FIG. 4 and the adjustment of speed may be wide enough to effect a 2 to 1 change, even using this adjustment in place of the switches 64 and 68 to effect the change from double to single thickness ice. Any known type of speed changing device may be likewise employed to modify the lengths of ice-making cycles.

. It is intended in FIG. 1 that the chutes 2.3 and 94 be made readily removable for cleaning the inside of the flue or sleeve Ill, in line with the previous mention of tube 29 or 26) being flexibly connected, as shown in FIG. 9.

The water tank 44 may likewise be removable separately from compartments 34 and 49, in which case care should be taken to keep the moisture which condenses on the outside of 3440 from dripping into tank 44. This feature is illustrated in FIG. 3 by the separation of drip water from circulating water, using the gutters 42 to catch the drip of water condensed from the air.

In making the water tank 44 separately removable it is also the plan to make the tube 96 FIG. 1), a tube connected with the inlet of pump 92, and the water supply tube leading to valve 104 come down into the tank from the top, also supporting the float valve from the top, so

that the tank 44 may be removed by dropping it away from these connections. Since the faucet 166 should be located some distance above the bottom of space 114, as shown in FIG. 4, there is room to drop the tank 44 and then remove it from the cabinet in a forward direction.

Another feature planned is to make the base pan 130 deep enough to hold all of the water which might overflow the tank 44 in the event of current failure which allows all of the ice to melt. No great depth is necessary for this, as the pan is practically the full size of the cabinet, extending almost to the outer walls at the rear and on the two sides. At the front it can extend as far forward as the bulge of the drawer front, thus providing the maximum of support to keep the cabinet from tipping forward when the freezer drawer is opened to its limit and heavily loaded. A part of the accidental ice meltage is cared for by having the float-controlled level some distance below the .top of the tank, as shown in FIG. 1. Where a single tank or flue is used, each of the two evaporators may be formed of a flat sheet, with or without fins attached to cool air, and a stamping which.

includes all of the embossed areas for ice making and all of the embossed passages for refrigerant flow, thus the two stampings can be identical.

The switches 65 and 68 may be thermally responsive and close on temperature drops of their bulbs instead of being actuated by the cam '70. In this case one of the switches will have its bulb quite near one of the icemaking areas to cause short cycles and the other will have its bulb located somewhat furtherfrorn an ices ga he making area to cause the longer cycles which produce the double-thickness disks. A double-throw switch will then replace 64 and be actuated by the weight of ice on shelf 60 to shift control to the thermostatic switch having the closer bulb when a full supply of double-thickness ice disks has been accumulated.

Still another method of control is to use a single thermostatic switch and arrange its bulb to be moved to the near position by the weight of ice on shelf 69. These modifications are not shown in the drawings, but it is believed that the above brief descriptions make it clear how they will fit into FIG. 1 or FIG. 4. Y

I claim:

1. In a refrigerator, a freezer drawer, an evaporator located above the closed position of said drawer, means for heating said evaporator to defrost it, a motor arranged to open said drawer, said motor being of a type not injured by being stalled, a stop to limit the opening of the drawer and thereby stall said motor, energy storage means energized by the opening of said drawer under the power of said motor, and control means for causing the defrosting of evaporator and simultaneously energizing said motor to open the drawer so that defrost water does not drip into it, said control means acting at the completion of the defrosting to de-energize said motor so that the drawer is reclosed under the effect of the stored energy.

, 2. In a refrigerator, a drawer, an inclined slide mechanism supporting said drawer and providing a path of movement in the opening direction which causes the drawer to drop slightly at the start of opening movement, then to rise on an incline so that when substantially fully opened the drawer is at a higher level than that of its closed position, means for opening said drawer to said higher level, from which position the drawer is self-closing when the opening force is no longer applied, manually actuated means for opening said drawer to a fully open position, and means for retaining it there independently of the opening force.

3. In a refrigerator, a drawer, a cooling element located in a fixed position in said refrigerator above the closed position of said drawer and open in the closed position of said drawer for circulation of air in contact with it and with goods stored in said drawer, a baffle in said drawer adjacent one of its vertical walls defining therewith a passage through which air may fiow upwardly from the drawer to said cooling element, a control for regulating the operation of said cooling element, and a thermally responsive element of said control located in the path of air flowing from the top of said passage toward said cooling element.

4. In a refrigerator cabinet, a drawer for the storage of frozen foods, an evaporator fixedly supported in said cabinet for cooling the contents of said drawer, power means for opening said drawer, heating means for defrosting said evaporator, a warning signal lamp arranged to be lighted when said drawer is opened, and control means periodically energizing said power means and heating means to defrost said evaporator while the drawer is open, said control means also regulating the ending of the defrosting operation and causing the drawer to be reclosed and the lamp turned off. 5. In a refrigerator, a drawer for the storage of frozen foods, an evaporator located above the closed position of said drawer, a motor arranged to open said drawer, heating means for defrosting said evaporator, and a time mechanism for simultaneously energizing said motor and said heating means to defrost said evaporator while said drawer is open and to reclose said drawer at the conclusion of the defrosting.

(References on followingpage) References Cited in the file of this patent UNITED STATES PATENTS Claassen Aug. 2, 1921 Richardson Oct. 14, 1930 Rosendahl May 2, 1933 Vretman June 29, 1937 Hudon Oct. 3, 1939 De Lisle Jan. 2, 1940 Paulson Nov. 27, 1945 Frie Mar. 1, 1949 10 18 Earle Apr. 26, 1949 Leutheuser Dec. 6, 1949 Dunlap Dec. 13, 1949 Nielsen Feb. 7, 1950 Dunlap Aug. 15, 1950 Robinson Jan. 23, 1951 Karp Aug. 14, 1951 Binder Nov. 6, 1951 Meek et a1 June 28, 1955 Tobey Oct. 4, 1955 Muffiy June 26, 1962 

5. IN A REFRIGERATOR, A DRAWER FOR THE STORAGE OF FROZEN FOODS AN EVAPORATOR LOCATED ABOVE THE CLOSED POSITION OF SAID DRAWER, A MOTOR ARRANGED TO OPEN SAID DRAWER, HEATING MEANS FOR DEFROSTING SAID EVAPORATOR, AND A TIME MECHANISM FOR SIMULTANEOUSLY ENERGIZING SAID MOTOR AND SAID HEATING MEANS TO DEFROST SAID EVAPORATOR WHILE SAID DRAWER IS OPEN AND TO RECLOSE SAID DRAWER AT THE CONCLUSION OF THE DEFROSTING. 